The brain encodes various information through the interaction between macro‐scale phenomena such as Local Field Potential and micro‐scale phenomena such as individual neuron action potential time series. However, the interaction between micro‐ and macro‐scale phenomena that affects episodic memory remains unexplained. We propose a new mathematical framework to predict the parameter conditions under which theta phase precession occurs by constructing models that reproduce the micro‐ and macro‐scale phenomena separately and deriving their phase equations. It was found that phase locking or phase shift between the micro‐scale phase ϕitalicmicro and the macro‐scale phase normalΦitalicMacro can reproduce different storage schemes. © 2023 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.

No abstract

Information processing in the brain is performed by the interactions of numerous number of neurons. However, much remains unknown about complex behaviors of a network composed of numerous number of neurons. Especially, in what case cross frequency coupling emerges and how it alters timings of individual firing are open questions. Therefore, in order to quantitatively evaluate the dynamics of the nervous group, we reproduced phenomena such as cross frequency coupling observed in the brain on a mathematical model and analyzed. The analyses of Fokker‐Planck equation provide the region of gamma/theta oscillations as well as their cross‐frequency couplings. In addition, we demonstrated that the populational oscillation synchronizes sequences of spike trains, which is supposed to be a possible mechanism of memory coding in hippocampus by theta‐gamma neural code.

This systematic review and meta-analysis examined the effects of neurofeedback training (NFT) on attentional performance in healthy adults. Six databases (PubMed, Scopus, Web of Science, PsycInfo, JDream&#8546, and Ichu-shi) were searched up to June 2022 for randomized controlled trials (RCTs) comparing attentional performance following NFT to a control group. Risk of bias was determined using the Cochrane Collaboration's tool. We identified 41 RCTs for qualitative synthesis and 15 RCTs without high risk of bias (including 569 participants) for meta-analysis using a random-effects model. The overall effect of NFT on attentional performance was significant (standardized mean difference = 0.27, 95% confidence interval = 0.10–0.44). However, approximately half of the studies did not compare its effects with sham-NFT, and no significant pooled effect of NFT was found in the studies compared to a sham-NFT group. Furthermore, subgroup analyses revealed variable effects on individual attentional performance subsets (executive function, spatial orientation, and arousal). Future large-scale sham-controlled RCTs are needed to confirm the efficacy of NFT for improving attentional performance.

No abstract